Dredging apparatus.



No. 780,027. PATENTED JAN. 1'7, 1905.

J. EDWARDS 6; W. H. GAHAGAN.

DRBDGING APPARATUS.

APPLIGATION FILED MAY 17, 1902 2 SHEETS-SHEET 1.

WITNESSES:

W 9. 4mm

No. 780,027. 7 PATENTED JAN. 17, 1905.

.T. EDWARDS & W. H. GAHAQAN.

DREDGING APPARATUS.

APPLICATION FILED MAY 17. 1902.

2 BEBETS-SHEET 2.

A TORNEY STATES JOSEPH EDWARDS, or BRQOKLYN,

Patented January 17, 1905..

NEW YORK, AND HALTER H. GAHA- GAN, OF BOONTON, NEW JERSEY.

' DREDGING APPARATUS- SPECIFIGA'IION forming part of Letters Patent No. 780,027, dated January 1'7, 1905.

7 To (IIZZ whom, it may concern.

Be it known that we, Jos urn EDWARDS,a1OSident of New York city, borough of Brooklyn, county of Kings, State of New York, and

5 WALTER H. GAHAGAN, a resident of Boonton, county of Morris, State of New Jersey, citi- Zens of the UnitedStates of America, have invented certain new and useful Improvements in Dredging Apparatus, of which the follow- I ing is a specification.

' Our invention relates to dredging or excavating of sand, gravel, or other materials for the purpose of reclaiming or filling in lowlying land, or for removing sand and gravel from the beds of rivers, lakes, harbors, &c.,

to use as building material and for other purposes, or for excavating in coifer-dams or places where it is desired to dig vertically and excavate material under water in a cheap'and 2O eiiicient manner, and for various other similar purposes.

The object and intention of our improvement is to direct the force of the currents of water entering the suction-pipe in such a man- 5 her that they will impinge upon or perform the act of scouring or eroding materials it is desired to dredge.

It is also our intention to produce a method whereby the suction end of the dredge or cen- 3 trifugal pump .may come in contact with the materials to be dredged and lie upon them -with its weight without the suction end being clogged or plugged from an excess of material and yet have the suction end remain in contact with the material to be dredged and preserve a uniform feed of nearly the capacity of the dredging-pump to raise and discharge.

With the ordinary centrifugal pump or dredging apparatus used for dredging sand,

4 gravel, and other materials from waters the plain suction-pipe, such as is commonly used, when placed in contact with the material to be dredged will quickly bury itself, so that the dredge-pump will become clogged, or the effect from the interruption of a uniform feed or a temporary breaking of the vacuum will cause a wrenching of or shock to the discharge-conduit that carries the dredged materials, making it almost impossible to main- Application filed May 17, 1902. Serial No. 107,796.

tain the discharge-conduit in proper condi- 5 tion. Also it is well-known that with the ordinary straight suction-pipe the feed is uneven and intermittent, so that the amount of continuous work performed is comparatively small. We aim to overcome these and other objections found to exist in the use of the plain straight single suction-pipe; and the invention therefore consists, essentially, in a conical or cylindrical hoodor envelop surrounding the mouth of the suction-pipe-and 6 firmly connected thereto in such a manner as to provide an annular space between the suction-pipe and the outer hood, said hood extending upward alongside of the suction-pipe from the mouth as far as may be necessary 5 to prevent that caving in of the materials around the mouth as will be likely to smother the suction and clog it from receiving the proper amount of water used in the process of hydraulic dredging; and the invention also 7 consists in numerous details and peculiarities of construction and combination supplementary to and in modification of the essential feature of the invention, substantially as will be hereinafter described and claimed.

In the accompanying drawings, illustrating our invention, Figure 1 is a side elevation of a dredging apparatus embodying our present improvements. Fig. 2 is a top plan view of the same. Fig. 3 is a detail view of the suc- 80 tion-pipe, its elbow, and the hood. Fig. 4 is an enlarged longitudinal section of the mouth of the suction-pipe, the outer envelop or hood, and the parts connecting the two. Fig. 5 is a transverse section on the line a: r of Fig. i. 5 Fig. 6 is a left-hand end elevation of the parts shown in Fig. 4. Fig. 7 is a partial longitudinal section of a modified form of suctionpipe. Fig. 8 is a cross-sectional view of the same. Fig. 9 1s a detail side view of the 9 we have delineated in Fig. 1 an outline view of a dredging-plant vessel or hull 1, on which is an engine 2, boilers 3, and dredging-pump l. Arranged in connection with the pump 4: and leading to the end of the hull 1 is a discharge pipe or conduit 5, which delivers the material that is brought up from the bed of the river by :meansiof the suction operation of the pump. 6 denotes the suction-pipe, connected to the pump 1 and running from the hull 1 forwardly rand downwardly into the water to the material to be dredged, and this suction may or may not have an angle within its length to give the end the proper inclination, so it may at all times be as nearly as possible normal to .the' surface of the material or bottom of .the waters to be dredged. Any suitable substantial form of boom, as 7, may be arranged to .swing at the end of the vessel 1 and is furnished with cables 8, connected to the sub- ,merged mechanism and used for the purpose of supporting, adjusting, and positioning the latter. It will be readily understood that the boat may be held in position by the use of swinging lines connected to the hull by winches and extending to anchors, or when practicable spuds can be employed for holding the hull in position, although if the suction-pipe is to be permitted to dig to its full depth spuds would be hardly permissible, and so it is better to use anchor-lines for controlling all motions. However, we reserve the liberty of employing either kind of device. In the length of the suction-pipe 6 at a point a convenient distance from its receiving-mouth we find it convenient to insert an elbow 12, having flanged ends 20 and stiflening ribs or webs 13. Angle connections 21 21, consisting of heavy cast-steel flanged and ribbed sleeves, which are turned and shrunk upon the ends of the suction-pipe 6, are used to connect said ends to the flanged ends of the elbow 12.

The lower or mouth end of the suction-pipe 6 is of any suitable shape and size. One convenient formis the flaring or bell-mouth shape indicated at 6 in Fig. 4. Another form which may be used when conditions require it is the oblong or oval mouthpiece 17 repre sented in Figs. 9 and 10. The suction-pipe 6 is surrounded by the conical or other shaped outer pipe or envelop 9, between which and the suction-pipe 6 is an annular space through which the water flows toward the mouth end of the suction-pipe in the direction shown by the arrow in Fig. 4c. The outer pipe 9 is held in position on the suction-pipe by means of the interior braces 10, which are clamped around pipe 6 and bolted to pipe 9, said braces being held together by bolts or rivets 11 passing through their contiguous parts. There may be any number of sets of these braces. In the drawings we have indicated two sets which are similarin construction. The lower periphery or mouth of the hood or outer pipe 9 may be flush with the mouth 6 or may be raised above or lowered below the plane of the mouth 6*, this being usually accomplished by changing the position of braces 10 as may be required. Adverting to Fig. 9, it will be observed that when the receiving-mouth 17 is of the oval shape the inclosing hood or outer pipe9 will be correspondingly oval or oblong in its form, as shown at 118 Another modification in the construction and shape of these parts is shown in Figs. 7 and 8, where a series of pipes or boiler-tubes 16 is arranged around the suctionpipe 15, the principle of operation being the same as of that form of hood shown in Fig. .2 or the form in Fig. 9.

In order to imparta clearer notion of the way in which the operation of .the dredging is performed by the mechanism set forth herein,

we will briefly discuss this operation. The dredge or plant for excavating will of course first be located in the position where the Work is to be done, the dredging or centrifugal pump then exhausted of air, and the machinery started. The suction-,pipe will be lowered into contact with the material or bottom, as shown in Fig. 1. The vacuum will be increased, and the pump will try to pick up the material to the extent of the capacity of the vacuum and the inrushing water to do so the instant the plain suction-pipe touches the bottom. By keeping the end of the suctionpipe in direct contact with the material it would quickly clog if it were not relieved, and the vacuum would be broken because of lack of water, and the pump would lose its charge. The necessary relief, however, is aflorded to the suction-pipe by the use of the hood or envelop, already explained. When the suction-pipe has its mouth 6 in contact with the material, obviously the water flowing to the suction-pipe will be cut off; but the pressure of water between the outer hood and mouth of the suction-pipe in the opening or space between said mouth 6 and the periphery of the lower end of the outer hood, aided by the vacuum, causes the suction-pipe to receive its necessary supply of water through this opening, and a Water circulation downward between the hood and suction-pipe is established. So long as the end of the suction-pipe is kept in contact with the matter to be dredged the suction-pipe will receive almost all of its supply of water through this annular opening and the power of the water in eroding material will be great. Further, the suction-pipe under these conditions will not be clogged by an uneven or unusually heavy feed of material, which clog if it occurred would clog the pump, for it is very desirable to keep the vacuum in the suction end and the pressure in the dischargepipe as uniform as possible. The suctionpipe is permitted to dig its Way downwardly, and the banks around it will erode or cave or may be caused to do so by the use of hydraulic jets or powerful water-giants. Since the suction-pipe will continue to be lowered as it digs deeper and deeper, the dredge may be kept at work in one position as long as sufficient material can be obtained from that spot, and the dredge will all the time be working at its full capacity without'any motion other than a slight raising and lowering of the suction-pipe.

Having thus described our invention, what we claim as new, and desire to secure by Letters Patent, is

1. In a dredging apparatus, the combination with, the suction-pipe, the mouth of which is adapted to lie upon the bottom ofthe place to be dredged, of an inclosing hood or envelop surrounding said suction-pipe for a certain distance and open at the ends, together with braces for supporting the envelop in place upon the pipe, said braces being adjustable so Witnesses:

JOHN H. HAzeLToN, M. L. SHAY. 

